The invention generally relates to suspension systems for overland vehicles of the type including a body-supporting frame and a wheel-supported axle, and more particularly to an improved, lightweight suspension unit which is economic to manufacture and simple to install.
Heretofore, it has been common practice to provide trailers and similar vehicles with suspension systems including coil springs, leaf springs, air springs and combinations of coil springs and leaf springs with air bags, sometimes referred to as air springs. Such systems are typified by suspension systems disclosed and claimed in applicants' prior U.S. Pat. No. 3,782,753 and application Ser. No. 401,241, now U.S. Pat. No. 3,866,894.
While the suspension systems of the type hereinbefore mentioned generally serve quite satisfactorily for their intended purpose, it has been found that it is desirable to further reduce the mass of suspension systems and to further simplify fabrication and installation procedures, in order to improve the efficiency of the systems. This need is particularly emphasized by the prevailing energy shortage which imposes on manufacturers the requirement that production techniques be refined, and further imposes upon truckers the requirement that the payload-weight to vehicle-weight ratio be maximized, in order to conserve energy.
It is, therefore, the general purpose of the instant invention to provide an improved suspension unit for overland vehicles which is simple and economic to fabricate and install, and which is of a relatively lightweight construction, whereby substantial savings in vehicle weight can be realized with an attendant reduction in energy consumption.